Renal artery stenosis is the narrowing of the renal artery, often caused by atherosclerosis or fibromuscular dysplasia. This narrowing of the renal artery can impede blood flow to the kidneys, resulting in poor perfusion of the kidneys, reduced kidney function, and possible renal failure.
A stroke is the clinical designation for a rapidly developing loss of brain function due to a disturbance in the blood vessels supplying blood to the brain. This phenomenon can be due to ischemia (lack of blood supply) caused by thrombosis or embolism, or due to a hemorrhage, highlighting the desirability for increasing the cerebral perfusion of a patient.
US 2009/0198308 to Gross describes apparatus including a sensing electrode configured to be implanted at a non-cardiac site in a vicinity of an aorta of a subject and to detect an electrical parameter of the aorta, and a control unit configured to receive the detected parameter and to generate an output in response to the detected parameter. Additional embodiments are also described.
US 2009/0198097 to Gross describes apparatus for treating erectile dysfunction of a subject. The apparatus includes one or more electrodes configured to be coupled to a vicinity of a blood vessel that carries blood into or out of a penis of the subject, and a control unit configured to facilitate erection of the penis by peristaltically pumping blood in the blood vessel by stimulating nitric oxide (NO) production in the vicinity, by driving the electrodes to drive a current into the vicinity. Additional embodiments are also described.
PCT Publication WO 07/013,065 to Gross describes a bifurcation stent comprising one or more electrodes, the stent configured to be placed in a primary passage and a secondary passage of a blood vessel, and a control unit, configured to drive the electrodes to apply a signal to a wall of the blood vessel, and to configure the signal to increase nitric oxide (NO) secretion by the wall.
U.S. Pat. No. 6,616,624 to Kieval describes devices, systems and methods by which the real or apparent renovascular perfusion and intrarenal pressure may be selectively and controllably increased. The Kieval patent states that by selectively and controllably increasing renovascular perfusion and interstitial hydrostatic pressure when the heart is unable to pump sufficient blood or when renal perfusion is suboptimal, neurohormonal activation and fluid retention is reduced or reversed, thereby minimizing their deleterious effects on the heart, vasculature, kidneys and other body systems.
US Patent Application Publication 2004/0054384 to Nachum et al. describes a treatment method and device for promoting a localized increase in the flow of blood through a blood vessel in an area of the body, the method including the steps of: (a) providing a system including: (i) at least a first electrode operatively contacting a first portion of body tissue; (ii) at least a second electrode operatively contacting a second portion of body tissue; and (iii) a signal generator, operatively connected to the first electrode and the second electrode, for providing a plurality of electrical impulses to the electrodes; (b) applying the electrical impulses so as to subject the muscular tissue to at least one voltage differential, thereby inducing repeated, contracting, directional movement of muscular tissue associated within the blood vessel, so as to produce a localized increase in the flow of blood through the blood vessel.
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